#include <stdio.h>

int main(void) {
  int x;
  long long y;
  double z;
  x = 5.0 + 6.9; // 隐式转换
  y = 1234567890123456789;
  z = -y; // 隐式转换
  printf("x = %d\n", x);
  printf("z = %f\n", z);
  return 0;
}

